Experimental model of generalized musculoskeletal pain (fibromyalgia) in rats through intermittent stress exposure

Objective. To develop the experimental model of generalized musculoskeletal pain (fibromyalgia) in rats using intermittent stress exposure. Material and methods. Experiments were conducted in 3 groups of animals: group 1 — intact control; group 2 — animals exposed to isolation, group 3 — animals exposed to isolation and repeated cold stress (RCS). We assessed pain response thresholds (PRT) using Randall-Selitto electronic algesimeter (IITC, USA), tactile sensitivity threshold (TST) — using von Frey esthesiometer with SupertipsTM filaments (IITC, USA) (diameter 0.8 mm, impact force 0.4-74 g). Measurements were performed 24 hours before experiment, 1, 7, 14 and 21 days after its completion. Results. An experimental model of fibromyalgia was developed using intermittent prolonged psychological and cold stress exposure. Conclusion. This study indicates validity of intermittent stress model as an experimental model of fibromyalgia for research of chronic pain mechanisms.